go-kit 简易图型验证码(验证码封装生成图形的是)

图形生成包使用的是 github.com/dchest/captcha，为了方便go-kit使用，我对期进行了一层封装。
封装之后的包在go-kit的架构里只用两行代码就可以搞定图型验证码的生成,刷新,验证等功能

$ go get github.com/icowan/kit-captcha使用

在您的应用启动http服务的初始化代码参考:

import ("context""net/http""os""github.com/dchest/captcha""github.com/go-kit/kit/endpoint""github.com/go-kit/kit/log""github.com/go-kit/kit/log/level""github.com/go-kit/kit/transport"kithttp "github.com/go-kit/kit/transport/http")func main() {var logger log.Loggerlogger = log.NewLogfmtLogger(log.StdlibWriter{}) var traceKey = "trace-id"opts := []kithttp.ServerOption{kithttp.ServerErrorHandler(transport.NewLogErrorHandler(level.Error(logger))),kithttp.ServerBefore(func(ctx context.Context, request http.Request) context.Context {ctx = context.WithValue(ctx, "context-trace-key", traceKey)return ctx}),}var ems []endpoint.Middlewaresvc := New(logger, captcha.NewMemoryStore(captcha.CollectNum,captcha.Expiration,), traceKey) // 不想看到日志的可以不加svc = NewLoggingServer(logger, svc)var prefix = "/captcha/"mux := http.NewServeMux()mux.Handle(prefix, MakeHTTPHandler(logger, svc, opts, ems, prefix, func(ctx context.Context, w http.ResponseWriter, response interface{}) (err error) {return kithttp.EncodeJSONResponse(ctx, w, response)}))http.Handle("/", accessControl(mux, logger))err := http.ListenAndServe(":8080", nil)if err != nil {os.Exit(1)}}func accessControl(h http.Handler, logger log.Logger) http.Handler {return http.HandlerFunc(func(w http.ResponseWriter, r http.Request) {if r.Method == "OPTIONS" {return}_ = level.Info(logger).Log("remote-addr", r.RemoteAddr, "uri", r.RequestURI, "method", r.Method, "length", r.ContentLength)h.ServeHTTP(w, r)})}

服务启动: go run main.go

$ curl http://localhost:8080/captcha/refresh/image{"captcha_id":"IOAUynIXiqfUs56dQgfg","captcha_url":"/captcha/IOAUynIXiqfUs56dQgfg"}生成图形验证码

拿到上面获取到的captcha_id在浏览器打开 http://localhost:8080/captcha/IOAUynIXiqfUs56dQgfg 就能展示出图形验证码。

可以传参数:

默认生成的图片是 160 x 80，您可以自己定义如:

http://localhost:8080/captcha/IOAUynIXiqfUs56dQgfg?w=320&h=120

验证图形验证码

结合到您的服务上进行验证:

svc := New(logger, captcha.NewMemoryStore( captcha.CollectNum, captcha.Expiration,), "trace-id")// 不想看到日志的可以不加svc = NewLoggingServer(logger, svc)// 使用验证 一般在中间件使用if !svc.VerifyCaptcha(ctx, req.Query.Get("captchaId"), req.Query.Get("verifyCode")) { fmt.Println("验证码错误")} 使用第三方存储

默认使用内存进行存储验证码信息，多个节点建议使用第三方存储方案。

我这里使用了一个单点或集群Redis都支持的包: github.com/icowan/redis-client，不喜欢的可以按照自己的需求实现一个就行，您自定义的存储方案只需要实现以下两个接口就行:

type Store interface {// Set sets the digits for the captcha id.Set(id string, digits []byte)// Get returns stored digits for the captcha id. Clear indicates// whether the captcha must be deleted from the store.Get(id string, clear bool) (digits []byte)}

以下是我使用Redis存储方案的参考:

redisstorage.go

import ("time""github.com/dchest/captcha""github.com/go-kit/kit/log""github.com/go-kit/kit/log/level"redisclient "github.com/icowan/redis-client")type store struct {rds redisclient.RedisClientexpiration time.Durationlogger log.Loggerprefix string}func (s store) Set(id string, digits []byte) {err := s.rds.Set(s.pre(id), string(digits), s.expiration)if err != nil {_ = level.Error(s.logger).Log("rds", "set", "id", id, "err", err.Error())}}func (s store) Get(id string, clear bool) (digits []byte) {v, err := s.rds.Get(s.pre(id))if err != nil {_ = level.Error(s.logger).Log("rds", "get", "id", id, "clear", clear, "err", err.Error())}if clear {//_ = s.rds.Del(s.pre(id))}return []byte(v)}func (s store) pre(id string) string {return s.prefix + id}func NewStore(rds redisclient.RedisClient, logger log.Logger, expiration time.Duration) captcha.Store {return &store{rds: rds,logger: logger,expiration: expiration,prefix: "captcha:",}}

使用存储方案参考

import redisclient "github.com/icowan/redis-client"rdsClient := redisclient.NewRedisClient(...)svc := New(logger, NewStore(rdsClient, logger, time.Minute5), "trace-id")尾巴

希望写的东西对你有用！